Related Experiment Video
Updated: Nov 22, 2025

Micro-dissection of Enamel Organ from Mandibular Incisor of Rats Exposed to Environmental Toxicants
Published on: March 29, 2018
Molar incisor hypomineralization, prevalence, pattern and distribution in Sudanese children
Hanna E Abdalla1, Amal H Abuaffan2, Arthur Musakulu Kemoli3
1Department of Orthodontic, Paedodontic and Preventive Dentistry, Faculty of Dentistry, University of Khartoum, P.O. Box 102, Khartoum, Sudan. hanoya8@hotmail.com.
Background:
Molar incisor hypomineralization (MIH) has serious impact on oral health-related quality of life for a child, due to its effects on tooth structure, aesthetics and behavior of the child. The current study was designed to determine the prevalence, pattern and distribution of MIH in school children in Sudan.
Methods:
This was a descriptive cross-sectional study involving 568 children, aged 8-11 years from schools in Khartoum State. Following the collection of their socio-demographic data, the children were examined for hypomineralization on the 12 MIH-index teeth, the pattern and distribution of the MIH. The data collected was analyzed to obtain descriptive statistics. The results related to the socio-demography and other dental-related factors were tested using chi-square test and Spearman Rank Correlation, with the significant level set at p < 0.05.
Results:
The prevalence of MIH in the study population was 20.1%. The majority of the participants had both permanent first molars (PFMs) and permanent incisors affected (12.5%). However, in 7.6% of the cases only molars were affected. Even though more maxillary teeth were affected when compared to the mandibular teeth, there was no statistical significant difference between the occurrence of hypomineralization on mandibular and maxillary molars (p = 0.22). Maxillary incisors were significantly more affected by MIH when related to the mandibular ones (p = 0.00). Demarcated opacities were the commonest pattern of MIH defects (69.9%) in the experimental group.
Conclusion:
The prevalence of MIH in Sudanese children was 20.1%. In both dental arches, the permanent molars and incisors were frequently affected, with the demarcated opacity type of MIH being the most common form of defect.
Related Concept Videos
Teeth
In the bud stage, the tooth germ (an aggregation of cells) starts to form in the developing jawbone. During the cap stage, the tooth germ differentiates into enamel organ, dental papilla, and dental sac, which will later develop into the tooth's enamel, dentin...
Tooth Anatomy
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or...
Assessment of the Mouth
Mouth Inspection
The inspection begins with visually examining the mouth for symmetry, color, and size.
Chronic Kidney Disease II: Clinical Manifestations

